4820 Registration books, account books, notebooks, order books, receipt books, letterheads, notebooks, diaries and similar items made of paper or cardboard, exercise books, blotting paper books, activity covers (loose leaf and non loose leaf), folders, file covers, multi page commercial form papers, books with carbon paper between pages, and other stationery supplies; Sample books, adhesive books, and book covers made of paper or cardboard: HS code chinese tariffs